Science & Technology in Action

What is meant by biodiversity?

Life on Earth evolves as a complex web of interdependent organisms, ranging from large plants and animals to micro-organisms. The variety or ‘diversity’ of these living things is referred to as ‘biological diversity’ or simply ‘biodiversity’. The term biodiversity can be applied both globally and locally. Global biodiversity depends on the biodiversity of all of its parts, whether these are considered as regions and countries or in terms of larger ecosystems such as oceans, rivers, rainforests, coasts and dry land of various kinds.

Human impact on the environment

Over the last few millennia humans have become the dominant species on planet Earth and have transformed it to suit themselves, usually without much thought for the health of the environment and ultimately for our own wellbeing. The Industrial Revolution, which began around 1760, had largely negative effects on the environment. Factories often caused pollution of air and water but they also provided jobs. In 1800 less than 10% of the world’s population lived in cities; today that fraction is over 50% and, in the case of the most developed countries, it is over 80%. In 1803 the global population reached 1 billion; today it is 7.8 billion.

Growth in environmental awareness

In the mid-twentieth century smog and river pollution were a fact of life in most capital cities, including Dublin, London and Paris. Eventually steps were taken to ban the use of smoky fuels and to prevent sewage and industrial effluent entering the rivers. There was a growing realisation that people are part of the biosphere and that we need to live in a more sustainable way. At the United Nations Earth Summit in 1992 the first Convention on Biological Diversity (CBD) was signed and four years later it was ratified by over 180 countries. Its purpose was to address the global decline in biodiversity caused by exploitation of natural resources, such as forests and fisheries, in unsustainable ways. Today all proposals for infrastructural projects are required to include plans for the protection of local habitats and biodiversity as well as the wider environment. In 2011 the Government published the second National Biodiversity Action Plan for the years 2011-2016. (A third plan was published in 2017). Each local authority draws up its own biodiversity action plan detailing how national and EU directives are to be implemented locally.